Just one day after Orica told the ASX it had no information to account for last week's share price gains, the company announced a $110 million acquisition.

But analysts doubted the climb in share price was related to Orica's purchase of specialty food and chemicals distributor Bronson & Jacobs.

In response to an Australian Stock Exchange "speeding ticket" on Monday, company secretary Michaela Healey made no mention of the chemicals and explosives producer's latest acquisition. Yet she acknowledged the Melbourne company made private presentations to analysts and international investors during the blackout period before half-year earnings are released on May 3.

Spokesman Stewart Murrihy said Orica's response to the ASX price query did not mention the acquisition because "the sale of [Bronson & Jacobs] was an incomplete proposal and confidential until signed by both parties".

Orica and Bronson & Jacobs said the 10 per cent share price rise last week was unrelated to the deal, which was finalised late Monday night and signed yesterday morning.

"The purchase of Bronson & Jacobs is in keeping with our publicly stated intent that has been stated on numerous occasions that we wanted to grow our Chemnet business," Mr Murrihy said.

Orica's Chemnet division will now be the No. 1 food chemicals distributor in the Australian and New Zealand market.

Privately held Bronson & Jacobs is a leading supplier of Australian tea-tree oil and other essential oils to the world market. Orica hopes to capitalise on the company's strong foothold in Asia, including China. The company's management team will remain intact under the deal, which takes effect on June 1.

"We're a $200 million company and need to go to the next level." Bronson & Jacobs chief executive Bill McCartney said. "A quality company like Orica can take us to the next level."

Burdett Buckeridge Young analyst George Marias said Orica had performed "exceptionally well" over the past year, with the shares rising 60 per cent since April 2003.

"The price hasn't moved up as a result of the acquisition," Mr Marias said. "It's one of a number of acquisitions and expansions that the company is doing."

ASX spokesman Gervase Greene said on the basis of price alone, the deal did not look to be a material acquisition which would significantly affect Orica's share price, which is capitalised at $4 billion. He declined to discuss whether the ASX would question the company about the timing of the announcement.